The present invention relates to a process assessment tool and a process assessment method evaluating a load a manufacturing process for industrial products puts on the environment, and a storage medium storing the method.
At present, environmental consideration has been very important in a manufacturing process for industrial products. Electrical energy is mainly used as power source or heat source, so-called secondary energy, in current production plants. In addition, design of manufacturing process has usually placed emphasis on cost reduction in industry.
But, recently, there has been a growing interest in global environmental preservation. Therefore, it is indispensable that reduction of energy consumption and reduction of emissions of global warming gases and acidification gases are considered simultaneously.
As a result, it is important for a planned process or a current process: to perform simulation namely process assessment of an impact i.e. a load the process may put on the environment; to extract problems from the process; and to consider measures for improvement.
A cogeneration system (Hereinafter cogeneration system is referred to as SYSTEM.) is a system providing a part of electrical energy necessary for production from a private power generator using gas or oil. Furthermore, use of waste heat from the power generator will allow the system to reduce energy consumption. A total energy conversion efficiency of SYSTEM using gas as fuel is usually 70 to 80%, so that an environmental load is expected to lower by using SYSTEM.
But, in the manufacturing process, it was usually difficult to optimize a ratio between power purchased and power produced by the private power generator.
Factors of the environmental load are described, for example, as follows:
i) an energy amount which is used to produce secondary energy such as electricity and town gas used for a manufacturing process by using primary energy such as natural gas, heavy oil, light oil, lamp oil, gasoline, coal, and wood;
ii) an emitted amount of environmental load materials such as carbon dioxide (CO2), nitrogen oxides (NOx), sulfur oxides (SOx), which are produced when the secondary energy is generated and utilized by using the primary energy.
But, a method of power generation namely a power source construction varies depending on a difference among electric power companies (supplier), and a difference among areas electric power is supplied to (service area). Therefore, amounts of environmental load emissions and the component percentages also vary according to an electric power company and an area electric power is supplied to.
If the environmental load of manufacturing process will actually be calculated, it would be difficult for the load to be correctly calculated, because so many factors of the load are combined each other in complexity.
On the other hand, for an environmental load of manufacturing process to be improved, it is necessary that an environmental load of each step (operation or process), which constitutes a manufacturing process, should be considered. But, many manufacturing processes have more than 100 steps. Components of a product could be often manufactured in a variety of plants. This as well makes an assessment of an environmental load difficult.
The object of the present invention is to assess a real manufacturing process, and provide a process assessment tool, which allows a process design aiming at lowering an environmental load.
First, to accomplish the object, a tool is necessary for a process assessment of the present invention assessing a load a manufacturing process for an industrial product puts on the environment. The tool comprises the following elements:
(a) a database storing data of a first environmental load corresponding to each energy source, whose consumption produces the first environmental load;
(b) a data input unit, into which data of condition of the manufacturing process for the industrial product is entered;
(c) a data processing unit calculating a second environment load the manufacturing process for the industrial product produces, by using the data entered into the data input unit and the data stored in the database; and
(d) a data output unit for outputting a result calculated by the data processing unit.
Second, a method for a process assessment for an industrial product of the present invention. This method assesses a load a manufacturing process puts on the environment, by using a database storing data of an environmental load corresponding to each energy source, whose consumption produces the environmental load. The method comprises steps of:
(a) inputting a condition of the manufacturing process for the industrial product;
(b) calculating a second environmental load the manufacturing process for the industrial product produces, by using the condition of the manufacturing process and data of a first environmental load included in the database; and
(c) displaying a result the step (b) calculates.
Third, a storage medium storing a program a computer runs to perform the method.
The tool, the method, and the storage medium of the present invention provide useful information to a manufacturing process design, which aims to reduce an environmental load of manufacturing process, and contribute to accomplish the object.